The following descriptions and examples do not constitute an admission as prior art by virtue of their inclusion within this section.
In a seismic survey, a plurality of seismic sources, such as explosives, vibrators, airguns or the like, may be sequentially activated near the surface of the earth to generate energy (i.e., seismic waves) which may propagate into and through the earth. The seismic waves may be reflected back by geological formations within the earth, and the resultant seismic wavefield may be sampled by a plurality of seismic receivers, such as geophones, hydrophones and the like. Each receiver may be configured to acquire seismic data at the receiver's location, normally in the form of a seismogram representing the value of some characteristic of the seismic wavefield against time. The acquired seismograms or seismic data may be transmitted wirelessly or over electrical or optical cables to a recorder system. The recorder system may then store, analyze, and/or transmit the seismic data. This data may be used to generate an image of subsurface formations in the earth and may also be used to detect the possible presence of hydrocarbons, changes in the subsurface formations and the like.
The receivers may also detect noise generated from one or more seismic sources that are not part of the seismic survey. These noises may distort the acquired seismic data by, for example, overlapping with a main reflected seismic wavefield that is the aim of the survey's measurement. The noises may also reach the receivers from directions that are significantly different with respect to the main reflected seismic wavefield. For example, in a marine seismic survey, the noises may be generated by one or more seismic vessels operating adjacently to the area of survey.